“While the Windows Installer Cleanup utility resolved some installation problems, it sometimes damaged other components installed on the computer. Because of this, the tool has been removed from the Microsoft Download Center.”

We’re all adults here, and since we’re obtained a copy of MSICUU2.exe from elsewhere, let’s continue:

It’s as simple as selecting the package you want to “clean up”, and then clicking Remove.

Read the warning, and then click OK.

After a minute, the selected program MSI registry keys will be removed, and you’ll be able to install the MSI package you want.